Curious about what kind of cup your LO uses and how old they are? We were told NOT to use sippy cups by our community health nurse due to possible tooth erosion? So we were using a straw cup - she's learning quite quickly how to use this. Then I heard from my SIL today that her doc said not to use them because it may impede their speech development? Doesn't make sense to me, but I'm willing to look into it more. So that basically leaves a plain cup, which is fine, she does well with one, but I can't let her use it on her own, obviously.

So what do you use, and why?